arc: Use GET_INTERFACE_FOR_METHOD macro

chrome/browser/chromeos/arc/arc_auth_service.cc

Index: chrome/browser/chromeos/arc/arc_auth_service.cc
diff --git a/chrome/browser/chromeos/arc/arc_auth_service.cc b/chrome/browser/chromeos/arc/arc_auth_service.cc
index 3440767dea4be965855db4e8c848c1b36d1d6870..658797975a9cd66dae70df6f56ee5e80e94985e2 100644
--- a/chrome/browser/chromeos/arc/arc_auth_service.cc
+++ b/chrome/browser/chromeos/arc/arc_auth_service.cc
@@ -27,8 +27,6 @@ namespace {
 
 ArcAuthService* g_arc_auth_service = nullptr;
 
-constexpr uint32_t kMinVersionForOnAccountInfoReady = 5;
-
 // Convers mojom::ArcSignInFailureReason into ProvisiningResult.
 ProvisioningResult ConvertArcSignInFailureReasonToProvisioningResult(
     mojom::ArcSignInFailureReason reason) {
@@ -145,7 +143,7 @@ ArcAuthService* ArcAuthService::GetForTest() {
 }
 
 void ArcAuthService::OnInstanceReady() {
-  auto* instance = arc_bridge_service()->auth()->GetInstanceForMethod("Init");
+  auto* instance = GET_INSTANCE_FOR_METHOD(arc_bridge_service()->auth(), Init);
   DCHECK(instance);
   instance->Init(binding_.CreateInterfacePtrAndBind());
 }
@@ -173,8 +171,8 @@ void ArcAuthService::RequestAccountInfo() {
 
 void ArcAuthService::OnAccountInfoReady(mojom::AccountInfoPtr account_info) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  auto* instance = arc_bridge_service()->auth()->GetInstanceForMethod(
-      "OnAccountInfoReady", kMinVersionForOnAccountInfoReady);
+  auto* instance =
+      GET_INSTANCE_FOR_METHOD(arc_bridge_service()->auth(), OnAccountInfoReady);
   DCHECK(instance);
   instance->OnAccountInfoReady(std::move(account_info));
 }